yep, someones 'upgraded' you.
I'm pretty sure that to fix it 'correctly' you need to re-install windows using the correct recovery partition/disk. not particularly fun but TBH in most cases you will see a perf benefit as you will only re-install teh stuff you currently use rather than teh crap that you have accumulated over teh years. this will seem to make windows much quicker.
Such is teh joys of different levels of Windows with different features.
You see with Linux you get teh full fat, fully featured version irrespctive of what you install or what you install it on.
